1. Field of the Invention
The present invention pertains to communication networks, and in particular to method for linking subscribers to plural communication networks via a local exchange.
2. Discussion of the Related Art
Public network operators currently have an almost monopolistic position in the area of telephone communications, which they will lose with the deregulation of telecommunication markets. In the future, free competition will exist in such a way that individual telephone customers can select the provider he finds most attractive with respect to scope of services, fee structure, etc. With regard to telecommunication infrastructure in general, several public networks can exist alongside one another, comprising the classical network operators and as they have developed historically, and the new networks of the alternative and newly added network operators. Such competing public networks will consist of long distance carriers, local exchanges, and linked transmission paths. Competing network operators will be positioned to optimize the access to the local exchange. In addition, the local and long distance exchange function can be combined into single exchange using gateways between the various public networks. Thus, the accessibility of the subscribers of any network is assured for any additional network.
Such exchanges, particularly local exchanges, consist of peripheral installations formed either as terminal installations for subscribers or as subscriber terminal lines. Furthermore, central installations, field installations, signaling installations, such as Signaling System 7 (SS7), message buffers, computer platform, background memory, operator installations, and competing network operators are also provided. As a rule, all these installations are software-controlled single-processor or multiple-processor systems.
At present, the great majority of subscribers are still connected via subscriber interfaces to local exchanges, or to pre-positioned competing network operators associated with these exchanges provided by the network operator. In the latter case, the interface between the subscriber terminal concentrator and the local exchange is not standardized (e.g. by the ITUxe2x80x94International Telecommunication Union), but is a manufacturer-specific interface. Finally, subscriber terminal lines usually lead to the main distributor of the local exchanges of the network operator in a costly manner, such as via underground cabling.
In the past, for a subscriber connected to a public network operator and desiring access to an alternative network operator, the subscriber terminal line would have to be disconnected at the main distributor of the local exchange of the previous public network operator, and supplied to the local exchange of the desired network operator. However, the problem arises that a procedure of this sort can only be carried out for all subscribers associated with the interface, because such procedure for individual subscribers is not possible due to the fact that installation expenses are enormous.
It is an object of the invention to provide individual free access to local exchanges of all alternative network operators so that subscribers can be connected to a desired local exchange via manufacturer-specific interfaces in a technically flexible manner without a large installation expense.
It is another object of the invention to provide that subscriber voice and signaling messages can be switched to a competing network operator in transparent fashion by means of at least one local exchange of a physically allocated network operator so that no expensive or rigid access paths is needed in the region of the competing network operator. In addition, no overdimensioned access paths have to be made from the competing network operator to the local exchanges of alternative network operators. In addition, fluctuating access needs of the local exchanges of the competing network operators, which are subject to unforeseeable market conditions, can be flexibly adapted by administrative means.
It is a further object of the invention to provide that in the local exchange of one network operator, the physical address given to signaling messages is examined to see whether the subscriber is designated for switching to another network operator, such that branching to the local exchange of the other network operator can take place immediately and without expensive internal analysis.
It is an additional object of the invention to provide in a table of the local exchange of a network operator, a conversion carried out between a physical address valid between the subscriber and the local exchange of a physically allocated network operator, and an address under which signaling messages are sent to the interface via which the local exchange of at least one of the additional network operators can be reached. Therefore, distinct addresses can exist that can be coordinated and flexibly adapted to one another between the competing network operator and the local exchange.
It is yet another object of the invention to provide that packet data sent from or to a subscriber is conducted via a peripheral installation that terminates a packet data channel and transports the packet data to the interface between the local exchange of a physically allocated network operator and a local exchange having the switching-oriented function. Therefore, ISDN subscribers are supported with packet data authorization.
It is yet a further object of the invention to provide that in the case of failure situations or reavailability situations in a competing network operator, or at the interface at the subscriber side, the local exchange of the physically allocated network operator can send port-specific failure messages or availability messages to the associated local exchanges of the additional network operators for all subscribers concerned and at all relevant interfaces for this set of subscribers. In the case of failure situations or reavailability situations at the interface at the operator side, the local exchange carries port-specific failure indicators or availability indicators for all subscribers concerned, thereby avoiding switching-oriented dummy loading.
It is yet an additional object of the invention to provide that the plurality of subscribers reaches the local exchange of the physically allocated network operator via a plurality of competing network operators and/or via a plurality of interfaces. In addition, with respect to signaling information, voice information and packet data, is allocated to one or several interfaces of the local exchange of the additional network operator. Thus, subscribers allocated to the new network operator can be concentrated in the local exchange.
It is still another object of the invention to provide that at the local exchange of the physically allocated network operator there are several interfaces to a plurality of local exchanges of different additional network operators. Thus, an arbitrary number of additional network operators can be connected in the same way and at the same time, via the local exchange of the physically allocated network operator.
It is still a further object of the invention to provide that signaling and/or packet data are conducted to the plurality of subscribers already in the subscriber terminal concentrator, on fixed signaling channels and/or packet data channels reserved only for the subscribers allocated in switching terms to the additional network operator. The fixed signaling channels and/or packet data channels are connected as a totality, via an internal message buffer system of the local exchange or via voice channel through-switching through the local exchange, to a signaling data channel and/or packet data channel of the interface at the operator side. Thus, a need to evaluate addresses in the local exchange is omitted.
It is still an additional object of the invention to provide that the local exchange controls a traffic measurement in the sense of counting the number, duration of voice channel through-connections and/or number and length of transmitted packet data, and/or signaling messages between the plurality of subscribers and the additional network operator as a basis for cost accounting between the network operators. The network operator can thereby substantiate to the other network operators use of the resources of the local exchange, and can request appropriate payment.
It is another object of the invention to provide that the table of the local exchange can be administered by means of user intervention, in such a way that a subscriber can be allocated, in terms of switching. Thus, to the network operator or to one of the additional network operators the interface, as well as the allocated signaling data channels and/or packet data channels and the address valid at the interface, can be freely allocated. Therefore, the subscriber can change the network operator responsible for him in terms of switching through user actions, and in a short-term manner as desired. Rewiring or other installation expenses are thereby not required.
It is a further object of the invention to provide that a plurality of subscribers way include subscribers who are connected to the local exchange of the physically allocated network operator via standardized interfaces V5.1 according to ETSI 300324 and V5.2 according to 300327. The standardized interfaces serve as signaling protocols and switching interfaces at the digital exchange for support of access networks, and that the signaling information and packet data information thereof are converted in a suitable way in the local exchange. Thus, subscribers connected to the local exchange in newer technology according to the V5 standard can freely choose the network operator responsible for them in terms of switching.
These and other objects of the invention will become apparent after careful reading of the following detailed description of the presently preferred embodiments which are to be read in conjunction with a equally careful review of the accompanying drawing figures.